The present invention relates to a package for flat recording media, e.g., video or audio cassettes or compact discs, which package has the form of a case composed of two parts joined by a hinge and completely enclosing the recording medium. The case contains a holder to receive the recording medium in such a way that it presents the recording medium when a closure is disengaged. A package of this type is disclosed in GB-A No. 2,154,550.
This prior known package consists of a plastic part made of polypropylene, with two parallel weakened lines serving as a hinge and defining between them a spine on the plastic part. The sides of the plastic part then form the upper and lower parts of the case.
Plastic strips running around three sides, which may be applied to the margins of the upper and lower parts, serve to form a caselike package with closed sides and to reinforce the upper and lower parts. A holder attached to the spine serves to receive the recording medium.
Due to the planar attachment of the back of the holder to the spine of the plastic part between the hinge lines, the holder exhibits a "pickup effect" when the upper and lower parts swing open, inasmuch as the holder swings up to a greater or lesser distance out of the lower part and away from the portion of the case formed by the lower part and its associated border. This intentional effect necessarily depends to a considerable extent on the weight of the recording medium, on operation by the user, and on the elastic properties of the plastic part in the region of the hinge lines. In the case of soft plastic material, the "pickup effect" described is necessarily rather weak, so that a specific operation is required of the user in order to raise the holder with the medium out of the lower part of the case. To be sure, this "pickup effect" is stronger in the case of harder plastic material, but the harder material is correspondingly more brittle and will experience fatigue sooner so that a case made of this material will have a shorter service life.
Since, therefore, the "pickup effect" is determined to a considerable extent by the selection of the material for the plastic part, it follows that it will also be affected by the external factors that effect the behavior of plastics, e.g., temperature or humidity, which will likewise affect the "life expectancy" of the hinge line.
All of these factors and interactions have the effect of precluding the creation of a definite presentation position when the package is opened.
Opening the prior known package is effected in that the frame that runs around the edges is contoured at least at some places in such a way that they interengage, thus achieving a catch closure due to friction. The structure of this catch closure in turn cannot be independent of the choice of material for the plastic parts and must take account of the resiliency force of the hinge lines, which force will tend to swing the case open. Independent of this, however, two hands are required to perform an initial opening procedure on this catch closure before the case more or less automatically presents the recording medium in a partially or completely suitable position for removal in the manner described above.
DE-A-13,247,796 likewise discloses a storage device for discoid recording media, but relates to a multiple package in which a complicated mechanism causes a fanlike arrangement to swing out. All of the components must be constructed in a relatively stable fashion, for example in order to contain the large moments of torque arising when the arrangement swings out. Finally, there is the structural complication created in this case by the kinematically unfavorable disposition of a coiled compression spring at the side of the case.
Compared to the arrangement disclosed in GB-A-2,154,550, the use of a separate elastic element in the structure of DE-A-13,247,796 does improve its swing-out behavior with respect to establishment of a definite position for removal but the design is obviously disproportionately complicated and expensive for use in a single package.